We hypothesized changes in the spatial organization of the trapezius muscle electromyographic (EMG) activity after a shoulder eccentric exercise. The rate of perceived exertion (RPE), the size of the soreness area, maximum force and, EMG from the upper, middle and lower trapezius were recorded. Root mean square (RMS), mean frequency (MNF) and normalized mutual information (a measure of functional connectivity between muscle sub-divisions) were computed during submaximal dynamic and static contractions performed before, immediately after and 24 h after exercise. Immediately after exercise, RPE, soreness area, RMS from the upper and middle trapezius and normalized mutual information among upper-middle sub-divisions increased while MNF decreased for the middle trapezius (P < 0.05). After 24 h, the maximum force decreased. RMS from the upper trapezius and normalized mutual information among upper-middle trapezius sub-divisions were higher than before exercise. MNF values increased from immediately after to 24 h after for the upper and lower trapezius (P < 0.05). The current results underlined changes in the spatio-temporal organization of the trapezius in response to shoulder eccentric exercise. The observed changes in EMG temporal and spectral contents and the enhanced sub-division coupling underlined the functional role of spatial variations of the EMG activity during muscle fatigue and in the presence of delayed-onset muscle soreness.

European Journal of PainVolume 13, Issue S1 p. S75-S75 233 STUDYING CHANGES IN PRESSURE PAIN TOPOGRAPHY OF THE TRAPEZIUS MUSCLE A.T. Binderup, A.T. Binderup Center for Sensory-Motor Interaction Dept. of Health Science and Technology Aalborg University, Aalborg E, DenmarkSearch for more papers by this authorL. Arendt-Nielsen, L. Arendt-Nielsen Center for Sensory-Motor Interaction Dept. of Health Science and Technology Aalborg University, Aalborg E, DenmarkSearch for more papers by this authorP. Madeleine, P. Madeleine Center for Sensory-Motor Interaction Dept. of Health Science and Technology Aalborg University, Aalborg E, DenmarkSearch for more papers by this author A.T. Binderup, A.T. Binderup Center for Sensory-Motor Interaction Dept. of Health Science and Technology Aalborg University, Aalborg E, DenmarkSearch for more papers by this authorL. Arendt-Nielsen, L. Arendt-Nielsen Center for Sensory-Motor Interaction Dept. of Health Science and Technology Aalborg University, Aalborg E, DenmarkSearch for more papers by this authorP. Madeleine, P. Madeleine Center for Sensory-Motor Interaction Dept. of Health Science and Technology Aalborg University, Aalborg E, DenmarkSearch for more papers by this author First published: 12 January 2012 https://doi.org/10.1016/S1090-3801(09)60236-6Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume13, IssueS1September 2009Pages S75-S75 RelatedInformation